In a challenging situation they may be under a rock ledge, behind a fallen tree, under sage and usually from a vantage point to watch their back trail, and from a downwind position. There may be a small group watching all directions. To find bedded deer, you should have a spotting scope and be prepared to spend hours spotting, traveling and looking.
If you hunting an area without much pressure, concentrate on locating feeding, travel routes and possible bedding areas. In mountain areas, they will be moving up hill early to bed in the thickest crap around. It really depends on where you are hunting, but spend time looking, spotting, locating water, food, bedding areas and travel routes.
If you find one bedded, it will be the toughest shot you will encounter. Pick a spot, practice and know your limitations. Their nose is key, avoid getting winded.